Acoustic motion determination

摘要

The motion of an object is characterized by transmitting acoustic signals over first and second transmitter-receiver channels. Information relating to signals received over the first channel is compared with information relating to signals received over the second channel, to identify a similar pattern in both channels arising from reflections from the object. A relative timing difference between the channels, associated with the similar pattern, is used to characterize the motion of the object.

主权项

1. A method of characterising the motion of an object comprising:
transmitting a plurality of acoustic transmit signals over first and second channels provided on a single device, said first channel comprising a first transmitter and a first receiver and said second channel comprising one of the three options comprising said first transmitter and a second receiver, a second transmitter and said first receiver, and a second transmitter and a second receiver; a first set of said transmit signals being reflected from an object in motion at a first set of times to form a first set of reflected signals; receiving said first set of reflected signals over said first channel; generating a first impulse response image comprising at least one of the group: impulse responses calculated from the first set of reflected signals; an offset, negated or linearly scaled transformation of impulse responses calculated from the first set of reflected signals; and an envelope of impulse responses calculated from the first set of reflected signals; a second set of said transmit signals being reflected from the object in motion at a second set of times to form a second set of reflected signals; receiving said second set of reflected signals over said second channel; generating a second impulse response image comprising at least one of the group: impulse responses calculated from the second set of reflected signals; an offset, negated or linearly scaled transformation of impulse response responses calculated from the second set of reflected signals; and an envelope of impulse response responses calculated from the second set of reflected signals; comparing the first impulse response image with the second impulse response image to identify, in the first impulse response image, a first pattern arising from the motion and, in the second impulse response image, a second pattern arising from the motion; and using one or more relative timing differences between the channels, associated with the first and second patterns to characterise the motion of the object as “Left”, “Right”, “Up”, “Down”, “Select” or “Too Vague”.